Need info about site intergration

[homerlex]

Hi - I am currently evaluating both phpBB and vBulletin. Both seems to be very good and though phpBB is free vBulletin is pretty inexpensive so cost should not be a big issue.

One requirement we have is that we need to be able to integrate a BB into our existing site so that users have a single signon (our site's login page). Instead of using the BB login page we would like to redirect to our own.

Now, with phpBB I was able to download the product, look at the source and db schema to determine what needs to be done. I do not have that option with your software.

Do you have any information available that what give me an idea what would need to be done to integrate vBulletin with our site? We currently use Java Servlets/EJBs. I know with phpBB we can read/modify the cookie that phpBB uses for sessions from our servlets. W can also create/modify phpBB user records from our EJBs.

I am assuming that the same is probably doable from vBulletin but I would need to see the code and schema to verify.
There is no way for me to see the code/schema without purchasing the software. How can I go about getting information about site integration?